Final answer:
To calculate the rate of return, we need to compare the amount your uncle is paying to the present value of the annuity. The rate of return would be approximately 7.12%.
Step-by-step explanation:
To calculate the rate of return, we need to compare the amount your uncle is paying to the present value of the annuity. The present value can be calculated using the formula: PV = PMT * ((1 - (1 + r)^-n)/r), where PV is the present value, PMT is the payment received each year, r is the rate of return, and n is the number of years. Plugging in the given values, we get:
PV = $15,000 * ((1 - (1 + r)^-12)/r) = $120,000
This equation can be solved to find the rate of return, which is approximately 7.12%.